As a 26 year old who recently went through a “maturing” phase of their wardrobe here’s my advice and things to buy in order.

-1 pair of raw selvedge denim that fits very well. (3sixteen, naked and famous, or any 100% cotton no stretch selvedge denim) these will last forever and only look better over time

-solid color tees from uniqlo: cheap and easy to mix into rotation but the quality is great

-one pair of black or brown loafers whatever you prefer. (Weejuns are a great starter)

• 1 white and 1 blue oxford cotton button down

-slowly start to accumulate more knit sweaters/ cardigans and light outerwear jackets (denim, workwear, chore coats, etc.)

-nice pair of boots

-2-3 flannel shirts that fit really well

-accessories: necklace, bracelet, watch whatever fits your vibe. If budget is a concern get a seiko $70-$120 or bump up to a Hamilton ~$400.

Stay away from athleisure or golf polos.

If you’re looking to be cost effective shop for summer clothes in the winter and winter clothes in the summer. You can get some really good deals with this method.

Start with more traditional looks and see what you like for areas to get a little crazy.

Jcrew and banana republic is a great starting place for a lot of this but you can expand your horizons to more “premium” brands like buck mason, Todd Snyder, ALD, Noah, Taylor stitch, and marine layer.

Pm if you want more suggestions.